I use~ 65 oz in micro digitals on the elevators (DS368) and a mini digital on the rudder (ds9411, ~85 oz in).

I can do anything at any speed with this setup. High speed parachutes, KE walls, KE loops, etc. If you're a sport flier you
can get away with less. If you set up the airplane so that you only have sport throws (no 3D rates), you could get
away with very small servos.

Standard servos (the $13 ones that come with radios these days) all around will fly this plane just fine with sport throws.